Auto merge of #26517 - nrc:fix-parallel-codegen, r=arielb1

Closes #26420

r? @nikomatsakis

src/librustc/middle/ty.rs

@@ -3283,6 +3283,7 @@ impl FlagComputation {
             }
 
             &TyClosure(_, substs) => {
+                self.add_flags(TypeFlags::HAS_TY_CLOSURE);
                 self.add_flags(TypeFlags::HAS_LOCAL_NAMES);
                 self.add_substs(substs);
             }

src/test/run-pass/parallel-codegen-closures.rs

@@ -0,0 +1,34 @@
+// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// Tests parallel codegen - this can fail if the symbol for the anonymous
+// closure in `sum` pollutes the second codegen unit from the first.
+
+// compile-flags: -C codegen_units=2
+
+#![feature(core)]
+#![feature(iter_arith)]
+
+mod a {
+    fn foo() {
+        let x = ["a", "bob", "c"];
+        let len: usize = x.iter().map(|s| s.len()).sum();
+    }
+}
+
+mod b {
+    fn bar() {
+        let x = ["a", "bob", "c"];
+        let len: usize = x.iter().map(|s| s.len()).sum();
+    }
+}
+
+fn main() {
+}